The candidate is a Hispanic female (U.S. citizen) from Santiago, Chile. I am clinically trained in cardiovascular medicine and have interest and expertise in heart disease in women. As a newly promoted Associate Professor at the University of California, Davis I have prior research experience in cellular and molecular biology investigating the actions of vasoactive peptides in endothelial cell growth and function in vitro. My clinical interest in estrogen as a modulator of cardiovascular risk and mortality in women, leads me to now seek to extend my prior research work in a new research direction to investigate mechanisms of hormonal regulation of vascular gene expression in atheroprotection. I am at a critical juncture in my career where clinical responsibilities threaten my future research progress. I need and seek protected research time and additional research training under the guidance of a mentor in three areas: [1] the use of murine models of disease, [2] molecular genetics, and [3] physiologic studies to investigate functional significance of genetic changes. To attain this goal I have enlisted the help of Dr. Stephen Barthold as mentor and Dr. Beverly Paigen as co- mentor. Dr. Barthold is an expert in mouse biology and directs the UCDavis Center for Comparative Medicine which oversees the Mouse Biology Program. Dr. Paigen has expertise in murine models of atherosclerosis and is a senior research scientist at the Jackson Laboratories. Together, we propose a research development plan with five components: [1] didactic course work at UCDavis, [2] didactic and hand-on laboratory work at the Jackson Laboratory, [3] participation in research seminars and lectures, [4] attendance at National and International scientific meetings, and p5[ a state-of-the-art hands-on research program. The research development plan provides seamless integration with the research plan. The overall goal of the research proposal is to understand the action of estradiol, the estrogen receptor, and estrogen/receptor interactions on atheroprotection, vascular function and gene expression in mice. Previous studies suggest the possibility of both receptor-dependent and independent mechanisms of atheroprotection by estrogen, yet surprisingly, genetic mechanisms of atheroprotection by estrogen have not been investigated and a suitable atherogenic mouse model has not been developed. In conjunction with physiological studies we wish to use established mouse genetic models, and create new genetically engineered models, in order to investigate the overall hypothesis that: [1] The atheroprotective action of estrogen is mediated by the estrogen receptor, and [2] The beneficial effects of estrogen are accompanied by expression of estrogen-sensitive genes that regulate atheroprotection in the vascular wall. To investigate this hypothesis we will pursue the following specific aims: [1] Develop an estrogen receptor alpha deficient and sufficient mouse model of atherosclerosis and characterize it by quantitative histology of atheroma and vasomotor tone using aortic tension assays in vitro. [2] Use the model developed in aim 1 to identify vascular genes that are up-regulated by estrogen by differential gene expression RNA fingerprinting by RT-PCR, and examine the role of selected other candidate genes that are likely to be influenced by estrogen (Ath 1, CASH, PAI-1, and aldose reductase) by Northern analysis. [3] Use molecular genetic methods for targeted deletion of mouse genes to determine the physiologic role of specific genes in newly created gene knock out mice, using the parameters optimized in Aim 1. The research and training environment available to the candidate for the conduct of these studies of vascular function and genetics is robust, the candidate's commitment is very strong, and the potential for success substantial. Advances in our basic understanding of mechanisms of hormone action could lead to more effective strategies for treatment of coronary artery disease in both men and women.